Grass mowing machines with reel mower cutting units are used on golf courses and other turf areas that require grass to be cut very accurately. The cutting units are typically mounted to a walk behind mower or rolled across the surface of the ground by a powered vehicle. The cutting units include a generally cylindrical reel with a plurality of blades that rotate in close proximity to a stationary bedknife fixed with the frame of the cutting unit. Grass is cut by a shearing action between the bedknife and the rotation blades of the reel.
Walk behind reel mower cutting units may ride on a traction drum and ground engaging roller, while reel mower cutting units mounted to vehicles may have one roller in front and another behind the cutting reel. The opposing ends of the front roller may be mounted to height of cut adjuster assemblies attached to the frame of the cutting unit. To change the height of cut, the operator may turn an adjustment screw on each assembly to raise or lower the front roller.
However, if an attachment with an auxiliary drive is installed on the reel mower cutting unit, it may be necessary to mount the front roller at a different position further from the cutting reel axis. Attachments such as conditioners, roller power brushes, or turf grooming brushes may be used to improve the quality of the cut, performance, and other turf grooming features. Attachments may be rotated by auxiliary drives mounted to the reel mower cutting unit and powered by the shaft of the cutting reel. An auxiliary drive may transmit rotational power from the cutting reel shaft to the attachment through a set of gears or a belt on a pair of sprockets or pulleys.
A conditioner, for example, is an attachment used for finer grooming of turf areas such as putting greens, by reducing thatch, slicing stolons, controlling grain, and deflecting material away from the reel and bedknife. A conditioner may stand the grass up for an even, clean cut and truer putting green surface. A typical conditioner includes a number of (for example, 72) closely spaced vertical blades mounted on a horizontal shaft adjacent one of the rollers. The blades may have a diameter of between about 40 and 80 mm, and preferably between about 50 and 65 mm. A conditioner may be counter-rotated to the direction of travel of the cutting unit. An auxiliary drive transmits rotational power from the cutting reel shaft to the conditioner. For example, an auxiliary drive for a conditioner may include a set of gears that rotate the conditioner at speeds of about 2000 rpm. The input shaft of an auxiliary drive may be removably connected to the shaft of the cutting reel, and the output shaft may be removably connected to the attachment.
When an attachment with an auxiliary drive is installed onto a reel mower cutting unit, the front roller must be shifted to a position further from the cutting reel. The conditioner or other attachment then may be installed directly in front of the cutting reel. Shifting the front roller to a position further from the cutting reel axis requires switching to a different height of cut adjuster assembly for the front roller. This is labor intensive and time consuming.
A height of cut adjuster assembly is needed for a reel mower cutting unit that may be used while a removable attachment such as a conditioner or rotary brush is installed on a reel mower cutting unit, and that also can be used if the attachment is removed. A height of cut adjuster assembly is needed that simplifies changing the position of the front roller relative to the cutting reel. A height of cut adjuster assembly is needed that reduces labor and time requirements for installing or removing an attachment onto a reel mower cutting unit.